Document WO2011151311 discloses a molding element for a mold for a tire comprising a tread provided with a plurality of blocks. Each block comprises a contact surface intended to come into contact with a road surface during running. The molding element also comprises a molding surface for molding the contact surfaces of the blocks. The molding surface comprises a plurality of fine lamellas intended to mold shallow sipes in the blocks. The shallow sipes improve the grip of the tire during rolling on icy roads. The fine lamellas are here made of aluminum obtained by molding from a plaster mold form. However, due to the weak dimension of the fine lamellas, obtaining molding elements with such fine lamellas using standard processes like milling, is difficult and expensive.
Document EP1641580 refers to a selective laser sintering method (SLS), in that document, a first layer of metallic powder is spread on a plate. All or some of the particles of this first layer of powder are then agglomerated by the beam of a laser according to the shape of the object that is to be obtained. The beam of the laser makes a plurality of round-trip passages to sinter the powder. Once this step has been carried out, a second layer of powder is spread over the first layer of powder and is, in turn, selectively fused by the laser. By repeating these operations of spreading a layer and fusing it using a laser, a sintered object is built up layer by layer.
A “tire” means all types of elastic tire whether or not subjected to an internal pressure.
A “tread” of a tire means a quantity of rubber material hounded by lateral surfaces and by two main surfaces one of which is intended to come into contact with a road surface when the tire is running.
A “tread surface” means the surface formed by those points on the tire tread that come into contact with the road surface when the tire is running.
A “mold” means a collection of separate molding elements which, when brought closer towards one another, delimit a toroidal molding space.
A “molding element” of a mold means part of a mold. A molding element is, for example, a mold segment.
A “fine lamella” of a molding element means a protrusion projecting from the molding surface, intended to mold a shallow sipe in the tire tread;
A “rib” of a molding element means a protrusion projecting from the molding surface, intended to mold a sipe or a groove in the tire tread. By “groove” or “sipe”, it is intended a cut with a width larger than or equal to 0.2 mm.